In the first study to experimentally investigate the phenomenon, researchers say it’s the unfulfilled ambitions of moms and dads that fuel their pushy parenting.

Tigers moms and sports dads, according to the investigation published in the journal PLOS One, are trying to mitigate their own failures by living through their children. That’s not entirely surprising, but, as study co-author Brad Bushman, professor of communication and psychology at Ohio State University says, “Our research provides the first empirical evidence that parents sometimes want their child to fulfill their unfulfilled ambitions—for example, that they want their child to become a physician when they themselves were rejected for medical school.”

The study, which was conducted in Holland, included 73 Dutch parents, mainly women, who were around 43 years old and had children between ages 8 and 15. Bushman and his colleagues asked the parents to complete a psychological test that measured how much they saw their children as part of themselves, rather than as entirely separate people.

Some of the participants were then asked to write about two life ambitions that they hadn’t realized and discuss why those goals were important to them. The rest listed two ambitions that their acquaintances weren’t able to achieve and wrote about the importance of these ambitions to those people. All of the parents then indicated how strongly they agreed or disagreed with statements like “I hope my child will achieve what I wasn’t able to achieve,” or “I hope my child will fulfill dreams I wasn’t able to fulfill.” This measured their desire to live through their children.

Those who saw their children most strongly as being part of themselves were more likely to want their kids to fulfill their dreams after thinking about their own failure — while those who saw their children as mainly their own people were not. And the more they saw their kids as part of themselves, the more they wanted their children to achieve their thwarted ambitions.

“When parents see their child as part of themselves, they may experience the child’s achievements as if they were their own,” says Bushman, “They may bask in the reflected glory of the child’s achievements. As such, the child’s achievements may become a surrogate for parents’ own unfulfilled ambitions. In this way, parents could lose some of the feelings of regret and disappointment that they could not achieve these ambitions themselves.”

Traditionally, psychologists have not viewed such “enmeshment,” in which people meld others into their self-perception, as being healthy, since it can lead to too much dependence. But studies found that people who reported seeing their partners as actually being part of themselves actually had closer and more satisfying relationships. Interdependence — not independence — may therefore be healthy.

But that may not be true of parent-child relationships, given the different positions that each holds in the hierarchy of the family. “[Enmeshment] is probably most unhealthy in relationships in which there is a large power imbalance, such as between a parent and child. However, research is needed to test whether this is true,” Bushman says.

Forcing children to pursue and fulfill dreams that aren’t their own can also have harmful consequences on the youngsters’ psychological development; children who are pushed too hard may react by developing depression or turning to alcohol and other drugs. “Several psychologists believe that, in very extreme cases, this desire could be harmful. For example, it may undermine children’s autonomy or put pressure on them to excel. But these ideas have never been tested in research studies,” says the study’s lead author, Eddie Brummelman, a PhD student at the University of Utrecht in the Netherlands.

But don’t most parents indulge in some form of projection, in part to teach and instill in their children a healthy desire to achieve? According to Brummelman and his colleagues, that can have some beneficial effects— at least on the parents. “Our findings provide novel insight into the joys of parenthood,” they write, suggesting that watching children excel in areas where parents were unable to could be healing. “Basking in children’s reflected glory, parents’ feelings of regret and disappointment may gradually resolve and make way for pride and fulfillment,” they say. The effects of that resolution on the children, however, may not be so positive.